Handcuffs



July 16, 1968 J. P. WILLI'AMSCIJN HANDCUFFS 3 Sheets-Sheet 1 Filed Oct. 19, 1965 5 Sheets-Sheet 2 J. P. WILLIAMSON HANDCUFFS 55gZ/Q645864-67 9 July 16, 1968 Filed Oct. 19, 1965 July 16, 1968 J. P. WILLIAMSON 3,392,554

HANDCUFF S Filed Oct. 19, 1965 3 Sheets-Sheet 3 14 E5. ll-

United States Patent ABSTRACT OF THE DISCLOSURE A handcuif with a bifurcated body and a pivoted C- shaped swinging arm with ratchet teeth has a cylindrical plug rotatably mounted in the body. The plug has an eccentric projection engaging, with clearance, a slot in a pawl slidably mounted in the body to engage the ratchet. A spring-controlled follower pin in the body engages in slots in the plug, which slots have ramps at one side to lift the pin. The plug has a keyway key which retracts the follower pin and moves tumbler pins in the plug to allow rotation.

The invention relates to improvements in handcuffs. In a known construction of handcuff there is provided a body having a projecting part which is bifurcated and C-shaped with a locking arm pivoted to the end thereof. The locking arm is also C-shaped and is capable of swinging in a complete circle, passing between the two arms of the bifurcated portion. The two C-shaped members combine to form a loop for engaging a persons wrist and the locking arm has ratchet teeth arranged to be engaged by a moveable pawl located in the body. The body has a keyhole for the insertion of a key of simple design and by turning the key the bit thereof may be engaged against a portion of the pawl so as to lift the pawl out of engagement with the ratchet and thereby enable the locking arm to be moved outwardly from the body to free the handcnif from a persons wrist or any other article with which it is engaged. This known form of handculf is also provided with a slide arrangedto be moved behind a portion of the pawl so as to prevent the pawlfrom moving away from the ratchet. This prevents the locking arm from being moved so as to restrict further the size of the loop made by it and the C-chaped portion of the body. The slide is normally moved by the insertion of the end of the key in an aperture in the body so as to engage a pin which in turn engages the slide.

A disadvantage of this known construction of handcuif is that it is relatively easy for the handcuff to be released using a picklock or other device. Even though the slide may have been applied, it is comparatively simple for an experienced person to insert a simple device such as piece of wire and manipulate it so as to move the slide away from engagement with the pawl and then to move the pawl using the same or another device inserted either through the keyhole or between. the teeth of the ratchet and the pawl. A further disadvantage of thisknown form of handcuif is that in order to move the slide to prevent further inward movement of the locking arm the key or some other devicefor engaging the slide is needed.

It is an object of this invention to provide handcuffs which are not subject to the disadvantages referred to above and with this object in view the present invention broadly resides in a handculf having a ratchet-engaging pawl controlled by a pin tumbler cylinder lock.

According to a feature of the invention the lock may be constructed and arranged so that it can be turned manually, without the aid of a key or any other device, so as to alter the handculf from a release handcuff condition to an applied handcuff condition and from the latter condition to a lock handcufi' condition, but cannot be turned manually from the lock handcufr' condition to the applied handculf condition or from the applied handcuif condition to the release handcuff condition. It is to be understood that in the release handcuff condition the locking arm is capable of being moved outwardly to release the handcuff from engagement, that in the applied handcufr condition the locking arm can be moved inwardly with the pawl sliding over the ratchet teeth and the arm swung in a complete circle to engage a persons wrist, while in the lock handcuif condition the arm is prevented from moving either inwardly or outwardly.

Other objects and features of the invention will be apparent from the following description of a preferred particular form thereof.

In this description reference is made to the accompanying drawings wherein:

FIGURE 1 is a perspective view of a pair of hand cuffs according to the invention,

FIGURE 2 is an enlarged fragmentary longitudinal sectional view of the body and associated parts of one of the handcuffs, the handcuif being in the release handcuif condition,

FIGURE 3 is an end view in the direction of the arrows 33 of FIGURE 2,

FIGURE 4 is a view in section on the line 4-4 of FIGURE 2,

FIGURE 5 is a view similar to FIGURE 2, the handcuif being in the applied handcuff condition,

FIGURE 6 is an end view in the direction of the arrows -66 of FIGURE 5,

FIGURE 7 is a view in section on the line 77 of FIGURE 5,

FIGURE 8 is a view similar to FIGURE 2, the handcuif being in the lock haudcuff condition,

FIGURE -9 is an end view in the direction of the arrows 99 of FIGURE -8,

FIGURE 10 is a view in section on the line 1010 of FIGURE 8,

FIGURE 11 is a view similar to FIGURE 8 with the key inserted,

FIGURE 12 is an enlarged fragmentary sectional view on the line 1212 of FIGURE 1,

FIGURE 13 is a perspective view of the lock plug of the handcuff, and

FIGURE 14 is a perspective view of a pawl of the handcuff.

Referring to the drawings a pair of handcuffs is provided, each handcutf comprising a body 21 of roughly rectangular form having a C-shaped bifurcated extension 22. The end of this extension 22 is bored to receive an axis pin 23 on which a locking arm 24 is mounted, the pin 23 being secured by a stud 25 engaged in an internal bore thereof. The locking arm 24 is engaged on a bearing bush 26 mounted on the axis pin 23 between the two portions of the extension 22 and is also C-shaped so as to form with the body 21 and extension 22 a complete loop to engage a persons wrist. The locking arm 24 is capable of moving in a complete rotation through the gap between the two arms of the body extension 22 and thus the handcuff can be applied in the normal way by engaging the exterior of the arm 24 against the persons wrist and causing the arm to move in a full circle to engage on the other side of the persons wrist.

The locking arm 24 is provided with ratchet teeth 27 arranged to be engaged by a pawl 28 mounted in a cavity 29 in the body. The said cavity 29 extends in a direction away from the location of the outer end of the body extension 22 and is of circular cross-section. The pawl 28 (which is shown separately in FIGURE 14) comprises a body of cylindrical cross-section adapted to slide within the cavity 29 and at its inner end it is provided with a cavity 30 in which there is mounted a helical compression spring 31 backing against a small plunger 32. The plunger 32 engages against the end face of the pawl cavity 29 and thereby urges the pawl towards engagement with the ratchet teeth 27. The direction of the ratchet teeth is such that when the pawl is engaged with the ratchet the arm 24 can move inwardly, i.e. to reduce the size of the loop, the pawl being lifted by the ratchet, but when it is attempted to move the arm outwardly the pawl engages the ratchet and prevents such movement. Portion of the pawl 28 is cut away near its outer end in order to provide a suitably shaped tooth 33 for engaging the ratchet, and a shoulder 34. A retaining pin 35 is inserted through the body 21 so as to engage against the shoulder 34 to limit the extent to which the pawl 28 can protrude.

The body 21 of the handcuff is provided with a further cylindrical cavity 36 opening to the pawl housing cavity 29, extending at right angles thereto and at right angles to the axis of rotation of the locking arm 24, and opening to the exterior of the body. This cavity 36 houses a lock plug or cylinder 37 which is shown separately in FIGURE 13. The lock plug 37 comprises a cylindrical body of a suitable size to fit within the cavity 36 and rotate therein, with a portion 38 extending outwardly and flanged and knurled in order to be conveniently gripped and turned by the fingers so as to rotate the plug. The inner end of the plug is provided with an integral eccentric pin 39 which engages in a slot 40 extending transversely in the pawl 28. The width of the slot 40 is greater than the width of the eccentric pin 39 and the various dimensions are such that when the plug is disposed so that the eccentric pin 39 is in its position nearest to the pawl retaining pin 35 (as shown in FIGURES 8 and 11) the pawl 28 is engaged by the eccentric pin so as to prevent the pawl being lifted out of engagement with the ratchet teeth 27 on the locking arm. Thus in this position of the plug 37 the locking arm cannot be moved either inwardly or outwardly, so that the handculf is in the lock handcuif condition. When the plug is turned through 90 (as illustrated by FIGURE the pawl is enabled to move to some extent from the position in which it engages against its retaining pin 35, and thus the pawl can be raised by engagement of the ratchet teeth with it and the arm 24 can be moved inwardly towards and through the bifurcated portion 22 of the body. When the plug is turned through a further 90 so that the eccentric pin 39 is in its position furthest from the pawl retaining pin (as shown in FIGURE 2) the pawl is withdrawn by the eccentric pin so as to be clear of engagement with the ratchet teeth and hence the locking arm can be moved freely in either direction. The handcuii is then in the release handculf condition. The plug 37 has an annular groove 41 of part circular cross-section and a pin 42 is inserted through the body 21 at right angles to the plug axis so as to engage in the annular groove 41 and thereby retain the plug in the body while permitting it to rotate.

The body is provided with a further cylindrical cavity 43 extending from the exterior parallel to the pawl cavity 29 and into the plug cavity 36. This additional cavity 43 houses a swivel 44 which has a cylindrical boss 45 with an intergral flange 46 and an integral eye 47. The boss 45 has an annular groove 48 of part circular cross-section and a pin 49 is inserted through the body 21 at right angles to the swivel boss axis so as to engage in the annular groove 48 and thereby retain the swivel in the body while permitting it to turn about its axis. The swivel 44 is connected by a link 50 to the swivel of an identical handcuff thus making up the pair of handcuffs.

The plug is provided with a keyway 51 which extends generally along a diametrical plane of the plug, the keyway being at the opposite side of the plug from the eccentric pin 39. As shown the keyway is provided with at least one deviation to prevent the insertion of a key other than one having corresponding deviations in its cross-section.

The plug is provided with three small cylindrical cavities 52, 53, and 54 extending at right angles to the axis of the plug and with their axes in the general plane of the keyway 51 but opening from the opposite side of the plug.

(While in this particular example there are three such cavities it will be understood that a greater number can be provided if considered desirable although the provision of a greater number will involve the size of the body, and therefore its weight, being increased.) The said cavities house tumbler pins 55, 56 and 57 respectively and are arranged to be aligned (in the appropriate position of the plug) with corresponding cavities 58, 59 and 60 respectively formed in the body and extending with their axes parallel to the axis of the pawl housing cavity 29. The cavities 58, 59 and 60 extend from the space between the commencement of the bifurcated portion 22 of the body 21 and house follower pins 61, 62 and 63 which are backed by helical compression springs 64, 65 and 66 and these in turn bear against plugs 67, 68 and 69 which may comprise steel balls retained in position by peening over the surrounding material of the body after the pins, springs and balls have been inserted. The follower housing cavity 58 nearest to the pawl housing cavity is spaced from the adjacent follower housing cavity 59 to some extent, and a further small cylindrical cavity 70 is provided in the body with its axis disposed between the axes of the two follower pin housing cavities 58 and 59 but at the opposite of the plug cavity 36, i.e. at the same side as the swivel housing cavity 43. This further small cavity 70 houses a further cylindrical pin 71 backed by a compression spring 72 and by a retaining plug 73 which is fixed in the outer end of the cavity.

A further pin housing cavity 74 is provided in the body 21 with its axis in alignment with the follower housing cavity 60, i.e. the one nearest to the outer end of the plug housing cavity 36. The pin housing cavity 74 is of larger diameter than the other pin housing cavities and it contains a cylindrical pin 75 of appropriate diameter backed by a further compression spring 76 which is retained by a further retaining plug 77 fixed in the outer end of the cavity 74.

The lock cylinder or plug 37 is provided with a pin receiving cavity 78 extending at right angles to the axis of the plug and with its axis in the central general plane of the keyway and in the same transverse plane as the pin housing cavity 70. Thus when the plug is disposed in the lock handcufi condition as shown in FIGURE 8 the pin 71 engages in the cavity 78 in the plug while at the same time the follower pins 61, 62 and 63 engage in the other three pin receiving cavities 52, 53 and 54 in the plug. Therefore when the plug is in this position and a key is not inserted the plug is prevented from rotating because of the position of the pin 71 and the three follower pins 61, 62 and 63. A key 79 of appropriate configuration is provided for use with the lock and when this is inserted, the serrated edge of the key engages against the tumbler pins 55, 56 and 57 thereby moving them and the follower pins 61, 62 and 63 so that their adjacent ends are located at the cylindrical surface of the plug as shown in FIGURE 11. At the same time, the back edge of the key 79 engages against the tumbler pin 71 at the opposite side of the plug andmoves it sothat the face contacting the back edge of the key is also at the peripheral surface of the. plug. The plug can then.be turned by the key through. 180 to the frelease handcuff condition shown in FIGURE 2 wherein the'pawl is lifted out of engagement with the ratchet teeth.

In order to provide for the removal of the key when the plug is in the release handcufi condition it is necessary that the design of the key79 rnust be such that the two innermost tumbler pins 55. and 56 do not require to be moved radiallyoutwardly beyond the peripheral surface of the plug during the withdrawal of the key. The tumbler pin 57 nearest to the outer end of the plug 37 can move radially outwardly from the plug as the key is withdrawn because it can make contact with the larger diameter pin 75 and displace the latter against the action of its spring 76 as thekey is withdrawn. If desired, similar larger diameter pins and backing springs may be mounted in the body oppositethe positions occupied by the other .two tumbler pins 55 and 56 in the release handcuff condition, therebyproviding for greater flexibility in the design of keys. However this would hardly be necessary since in general there would be no callfor a very large number of different key lock combinations.

Theplug is provided with two slots 80 and 81 arranged to co-operate with the innermost follower pin 61 during the rotation of the plug in order to control its manual movement without the key. The slot 80 is located diametrically opposite the cavity '52 for the innermost tumbler pin 55 and is provided with an abrupt shoulder at one side and an inclined ramp at the other side. Thus when the plug is in the release handcutf condition with the key removed as indicated in FIGURE 2 and FIGURE 4 the shoulder of the slot 80 engages against the follower pin 61 so as to prevent rotation in the clockwise direction as seen in FIG- URE 4 but permits rotation in the opposite direction by allowing the follower pin to slide along the ramp or sloping side of the slot 80. The slot 81 is of similar shape and is provided on the plug in the same transverse plane as the slot 80 but spaced by 90 so that at the end of 90 of movement of the plug from the release handculf condition the innermost follower pin 61 springs into engagement with this further slot as shown in FIGURES 5 and 7 and thereupon prevents reverse manual movement of the plug to the release handcuif condition due to the engagement of the pin 61 with the shoulder of the slot 81. When the slot 81 is engaged by the innermost follower pin 61 the handcufl is then in the applied handcuff condition in which the pawl 28 engages the ratchet teeth 27 but the locking arm 24 can be moved inwardly and swung through a full revolution to engage a persons wrist. The plug can be turned manually from this position in an anti-clockwise direction as viewed in FIGURE 7 through a further 90 to the lock handcuff condition shown in FIGURES 8, 9 and 10 in which the three follower pins 61, 62 and 63 all spring into engagement with their respective cavities in the plug 37 while the tumbler pin 71 at the opposite side of the plug also engages in its cavity. The handcuff is then in the lock handcuif condition and the plug cannot be moved any further except following insertion of the correct key.

As a precaution against the arm 24 being released from engagement with the pawl 28 in the applied handcuif or lock handculf condition by moving the portion of the arm bearing the ratchet teeth 27 in the general direction of the pivot pin 23, e.g. by reason of wear of the pivot pin or associated parts or by reason of distortion of the locking arm 24 and/ or body 21, an arcuate groove 82 coaxial with the pivot pin 23 is formed in one side face of the locking arm 24 and a check pin 83 is fixed in the body 21 so as to engage within the arcuate groove 82. Hence should an attempt be made to force the portion of the locking arm 24 bearing the ratchet teeth away from the pawl 28, this would be resisted by the check pin 83 engaging against the side of the groove 82.

To facilitate the correct setting and use of the handcuffs the end face of each plug 37 is marked with an arrow indicating the direction in which it is to be turned, and with a dot or other marking to be brought into alignment with other marks on the body 21 and to serve in conjunction with them to indicate quickly the condition of the handcuff. Preferably the words flock.;and set are marked on the body identifying the lock handcuff and applied handcuff positions.

I claim:

1. A handcuif comprising a body;

an arm pivotally connected to the body;

said body and arm forming a wrist-engaging loop;

a pawl mounted in the body and movable therein to engage the arm;

a cylindrical cavity in the body;

a cylindrical plug mounted for manual rotation in said cylindrical cavity among a plurality of positions including a first position and a second position;

cam engagement means between the plug and the pawl;

said cam engagement holding the pawl out of engagement with the arm in a first position of the, plug;

said cam engagement means forcing the pawl into engagement with the arm in a second position of the P means comprising at least one follower member mounted in the body and resiliently biased to engage the plug for preventing rotation from the second position to the first position while permitting rotation of it from the first position to the second position;

said plug having a keyway for the reception of a key to engage the follower member and disengage it from the plug and thereby permit reverse rotation of the plug from the second position to the first position.

2. A handcutf according to claim 1 wherein the arm has a plurality of ratchet teeth and the pawl is shaped to engage with said teeth to prevent movement of the arm in a direction to enlarge the loop, and wherein an inter-engaging connection between the plug and the pawl permits movement of the pawl into and out of engagement with the ratchet teeth when the plug is stationary in a position intermediate said first and said second positions thereof, said handcufi further including means for resiliently opposing movement of the pawl out of engagement with said teeth.

3. A handcutf according to claim 2, further comprising a tumbler pin cavity in said plug, and wherein said keyreleasable pin tumbler locking means comprises at least one follower pin mounted within the body and resiliently biased to engage in said tumbler pin cavity when the plug is in said second position, said plug having a first slot engageable by said follower pin when the plug is in said first position, said slot being defined by a first shoulder at one side thereof and a first ramp at the other side thereof, the follower pin being movable against its resilient biasing means by said first ramp when said plug is manually turned from said first position towards the second position.

4. A handcuif according to claim 3, wherein the plug has a second slot engageable by said follower pin when the plug is in a position intermediate the first and second positions thereof, said second slot being defined by a second shoulder at one side thereof and a second ramp at the other side thereof, the follower pin being moved against its resilient biasing means by said second ramp when the plug is manually turned from the said intermediate position towards the said second position.

5. A handcuff according to claim 2, wherein a plurality of tumbler pin cavities indent said plug, and wherein the key-releasable pin tumbler locking means comprises a plurality of follower pins mounted within the body and resiliently biased to engage in said tumbler pin cavities when the plug is in said second position, a plurality of tumbler pins being mounted one in each of the tumbler pin cavities, the handcuff being further characterised by a further pin housing cavity in the body in a position 7 wherein the outermost tumbler pin cavity is in communication with it when the plug is in the first position, and a further resiliently biased pin in said further pin housing cavity, said further pin and said further pin housing cavity beng of larger cross-section than said outermost tumbler pin cavity.

References Cited UNITED STATES PATENTS 985,560 2/1911 Widmayer 70-16 Latou 7016 Latou 7016 McKee 7016 Tompkins 7016 MARVIN A. CHAMPION, Primary Examiner.

E. J. MCCARTHY, Assistant Examiner. 

